Factors fun

Hello Barbara.

Hello Michelle. How are you?

I'm very well, how are you?

Very good thank you and we hope our mathematicians out there are also very good.

Um, let's play! You know how we played multiples madness recently?

Yeah.

Well this is a very similar game. In fact it's just based on reversing the idea of the game.

Oh, okay.

Yeah, so that we can practice thinking about division, while we're also thinking about multiplication. Right. So we've made our spinner, and this game we're not going to play blank. It's a blank version so you can make it what you like, and we're gonna do it based on fives today.

Okay.

And so what I did was write the product of multiplication using fives, up to 10 times 5. So you started from 5 and then counted by fives. Like 5 ones, 5 twos, 5 threes, 5 fours etc. And we spin the spinner like this, and now what I'm thinking about is 10 divided by 5.

Okay.

And in the same way you, like, if that would be 2, and so I have choices of where I put my 2.

Okay.

And today we're playing, so you get 4 in a row, but you only get 4 counters.

So you need to move them once you run out.

And a square counts.

Okay.

Okay? Four in a row, in any direction, or you can form a square.

But not like this?

No, not a square. Okay, your go.

So do I write for you and you write for me?

Yes.

Or do we write for ourselves?

Okay we're writing for each other.

Oops, okay, okay what do think? Spin again?

You choose.

Okay I want to go with 35.

Okay.

So 35 divided by 5.

Yeah.

And the answer is 7.

So I can choose any 7?

Any 7 you like.

I've got 2 choices so, both corners, so I'm turning over that one.

Okay.

Ok, your turn. Oh, I got 15 so 15 shared into 5 groups is equivalent to 3 in each group and I think I might go here.

Okay.

So you need to write for me. So you spun a 15. And then it was 15 shared into 3 groups, shared into 5! 5 groups, because we've always got 5 groups.

Your turn.

Come on spinner!

I know.

Okay, 40.

Okay, so you spun 40, what are you thinking?

Okay so I would, if I had tens, I'd need 4 tens. Oh yeah. That means I need 8 fives.

Yeah that's a nice strategy, I like that, using tens.

To help me with my fives. I just find tens quite easy, so.

Cuz of the place value?

Yeah so I thought I'd use that to help me with the 5 facts. 40 shared into 5 equal groups is 8 in each group.

Okay. Ohhh, 2 in a row already!

Watch out.

I got 35. And so 35 shared into 5 groups, well I know that 40 is 8. Yeah. So 1 less 5 is 35, so that must be 7.

And you also did it in the first round.

Oh and I did do in the first round.

For you, so, there's my only other choice of 7 actually.

So, 35 shared into 5 equal groups means 7 in each group. You can totally see why mathematicians invented that symbol.

It's really actually useful! Imagine having to write 35 shared into 5 equal groups is equivalent to 7 in each group.

Yeah, I like that mathematicians have developed, um, symbols. Your go.

Okay, okay thank you, historical mathematicians. Right! Okay, 20. Yep. Okay so, this one I know.

Yeah?

20 shared into 5 equal groups means 4 in each group. Now, I can't go this way. [pointing along bottom row] So, ohh, I don't, you know what, I like the middle.

Okay, I don't like that you like the middle of a board, cuz it's gonna be harder for me to win. But it'll also be hard for me to win if I use the bottom of the pencil to try to spin, see? Okay, 15. Well I actually know this too. I know 3 fives is 15 so 15 divided by 5 is 3. Ummm, and I am going to go, ohh there's only one other 3 left, so I have to go there.

Ohh and you got 3 twice.

I did.

Okay. 50.

50. Okay. That's a nice one.

Yeah, I know that 5 times 10 is 50.

Yeah.

So then 50 shared into 5 equal groups is 10.

Yeah.

Umm, now then, I might put it here because things could go my way, this way.

Oh yeah, it could.

Yeah more so than, ohhh. Oh no!!! [Points to another 10 in a better position.] That was silly wasn't it?

[No sound - video speeds up while they take turns]

And we only get 2 more spins to see if someone's a winner. Otherwise it's a tie.

Oh really?

Yeah.

Okay, so that was a 20 wasn't it? That you spun?

So sometimes, if you want, you could play with a fifth counter because that allows you a bit more freedom in moving things around. Because the 4 makes it, does make it harder.

It does make it quite hard. Yeah.

So we could introduce the fifth counter if you want on this spin?

Well if you've only got 2 spins left that's probably a good idea.

Yeah, lets do it. Okay.

You'll probably get a 6 anyway!

Oh no, a 3.

A 3. Okay, we just know the answer. 15 divided by 5 is 3.

Okay, oh okay but I can introduce a counter. So I'm just going to introduce a counter.

Okay, your turn.

I would have put it there, cuz then you needed a 9 or 6 to form another square.

That is totally a much better option!

Ummm, ohh, I think I'm gonna re-spin that. Sorry, cuz I wasn't really paying attention and it...

Uhhh, 40. Okay, so that's 8, cuz I know umm, 5 eights is 40 so I'm gonna put it here.

Okay, so.

Ohhh no, I'm gonna put it there.

Okay.

Or there? Or there?

Take your time Michelle. Quick game's a good game you know!

Umm, well if, I because if I was thinking if I go there, I can't like, oh there's one more spin right?

Only one more spin.

So I can't get 4 in a row there. But if I go there I still also can't 4 in a row so I might just go there.

Okay.

Can you record my move please?

Sure can.

Okay, so you really need 30.

Yeah, I wish I had... It's your only chance now.

Yeah, I think it is. It's also still my only chance.

Yeah.

Okay. And there's a 1 in ten chance of it happening. Okay.

Your go.

Come on, lucky last go! Come on 30! Oh, just short! Okay, so that's a 4. So 20 divided by 5 is 4. Where are the 4s? Oh hold on, I can't go.

Oh, so you miss a turn.

I was hoping I'd get another spin because I can't go.

Okay come on 6! Know what I'm gonna do is, start my spinner from a different spot.

Oh, still no go. And I would get a 4 and I also can't move.

So in this game we have tied, both losers.

Oh equal losers!

Over to you mathematicians, to have fun with factors!